ES2241256T3 - EXPRESS COFFEE MACHINE - Google Patents

Abstract

Espresso coffee machine comprising a pump (2) for pumping water in a heating chamber (3) and a valve unit (5) located downstream of said heating chamber (3) and connected to said chamber (3) of heating by means of a pipe (3¿) that ends in an upper opening of said valve unit (5), said valve unit (5) having a first lower opening that is in fluid communication with a pipe (5¿) of discharge and a second lower opening that is in fluid communication with a pre-infusion chamber (6), said pre-infusion chamber (6) being in fluid communication with the filter (8) via a pipe (6¿ ) of dispensing, the coffee machine comprising means (11, 14-15) for drying the coffee grounds that remain in the filter, characterized in that said means for removing residual water comprise suction means positioned along the pipe ( 5¿) download, in a intermediate position along it or downstream of the latter.

Description

Espresso machine

In its most general aspect, the present invention It refers to an espresso machine.

Dispensing devices in machines Known espresso coffee are based on structural configuration shown in figure 1a. A P pump pumps water through a heating chamber H, which can be heated directly by means of a heating element or indirectly by means of a heat exchange with the fluid in the steam generator C of Water. Once it has been heated, the water is pumped up to a valve unit V, from which it is transported to the filter F containing coffee powder. The coffee produced in this way is finally dispensed in a T cup through the holes made in the upper surface of the filter F.

During the dispensing process, the circuit of fluid between the pump and the filter (gray shading in the figure) is under a pressure of approximately 8-10 bar generated by the pump P.

Once the coffee has been dispensed, the valve cutout member V closes hole V1, cutting by this delivers the pressure from the pump to the filter. At the same time, hole V2 opens, putting the circuit downstream of the V valve in communication with the discharge S output, as illustrated in figure 1b. The pressure in that part of the water circuit below the hole V1 thus falls to atmospheric pressure and Coffee is not dispensed anymore.

In recent years there has been a great diversification in the types of coffee blends used in various countries and even in the various regions in Italy. These vary from abundantly toasted mixtures (dark beans) preferred in southern Italy, to lightly toasted mixtures (light grains) generally used in northern countries. It has been observed that, especially in the case of the latter, there is a inconvenient: muddy coffee grounds remain in the filter once That coffee has been dispensed. Remove and clean a filter that Contains coffee grounds in this state is unpleasant and does more Hard to keep the machine clean.

All of these have been thoroughly examined in this way. the stages of the process in order to discover the cause of this problem and it has been found that the phenomena that take place in that area of the circuit downstream of the valve unit V depend on the thermal conditions under which the system.

The water temperature contained in that part of the circuit between filter F and discharge outlet S (gray shaded portion in figure 1b), once complete The dispensing process depends on the various methods of dispensing employees and the different coffee blends used in The various regions of consumption. Those temperatures may vary. from 90ºC for a long espresso coffee (around 120 cc in the cup) produced by a light blend typical of the countries of the Northern Europe, up to 102 ° C for concentrated espresso coffee (about 20 cc in the cup) produced by a mixture abundantly toast typical of the southern regions of Italy. Yes wastewater in the downstream area of the valve unit V is at a temperature equal to or greater than its boiling point at atmospheric pressure (≥100 ° C), a vapor pressure of water that forces the water towards the discharge outlet S and consequently it causes coffee grounds to dry. Needless say that completely dried coffee grounds can be removed easily from the F filter, which is then ready immediately To be used again.

On the other hand, when the temperatures of operation is lower - as is the case with coffee produced using lightly toasted mixtures - not enough water is removed residual and coffee grounds remain like a wet sludge, as already Has mentioned. What's more, the problem is often compounded by the presence of a chamber I between the valve unit V and the filter F, whose camera is necessary to carry out the process of pre-infusion Really, it can contain a considerable amount of water in this chamber.

Patent publication EP-A-0465877 discloses a valve discharge for wastewater, but does not provide means to dry the coffee grounds.

The problem that has come to light is, so therefore, to prevent coffee grounds from forming a sludge that is difficult to remove once the coffee has been dispensed.

This problem has been solved by espresso machine as detailed in the claims attached.

Advantages and additional features of the espresso machine forming the object of the present invention they will become more clear from the description of a number of preferred embodiments given subsequently to non-limiting example mode and with reference to the following figures:

Figure 1a illustrates a schematic view in cutting of an espresso machine according to the technique previous;

Figure 1b shows the view of Figure 1a in a different stage in the operation of the apparatus;

Figure 2 illustrates a schematic view in cutting of an espresso machine in accordance with this invention;

Figure 3 shows the view of Figure 2 of according to a preferred embodiment of the present invention.

With reference to figure 2, the coffee machine express that forms the object of the present invention comprises a dispensing device 1 contained within a cover that It is not shown in the figure.

The dispensing device 1 comprises a pump 2 that draws water from a tank (not shown) or directly from the general water line and pumps it, via the pipe 2 ', to a heating chamber 3 in which the water is heated up to the desired temperature by means of suitable heating elements arranged around this heating chamber or, preferably, by means of heat exchange with the water vapor created by the water vapor generator 4. The water steam generator 4, in turn, preferably uses heating elements to convert independently supplied water into steam.
to the.

The flow of pump 2 and the capacity of the heating chamber 3 dictate the amount of time that water remains within said chamber 3 and therefore its final temperature

The hot water is transported then through the pipe 3 'to the valve unit 5 consisting of a body that has a top opening that is in communication of fluid with the 3 'pipe, a first lower opening that is in fluid communication with a 5 'discharge pipe, and a second lower opening which, through a 5 '' pipe joint, puts the valve unit 5 in communication with the chamber 6 of pre-infusion

A 7 'cutting member (for example a member fungiform cutting) is movably housed in said opening top of valve unit 5. A second 7 '' cutting member (which may also be, in this case, a fungiform member of cut) is movably housed in the first lower opening of valve unit 5. The valve unit 5 is made function, mechanically or electrically, by means of an actuator that It has not been shown in the figure.

The pre-infusion chamber 6 is, through the 6 'dispensing pipe, in fluid communication with filter 8 that is designed to contain the coffee mixture. The filter 8 is housed in a filter holder 9 which is fixed in detachable form to the machine at the point where the opening to dispense hot water. The filter holder 9 has a handle 10 in order to facilitate its attachment and removal of the machine. 9 'holes, through which the infusion of coffee, they are made on the bottom surface of the filter holder 9.

The espresso machine described above It is known.

The espresso machine that forms the object of the invention incorporates the innovative feature of having means to dry the coffee grounds that remain in the filter 8. In the practice, these means consist of means to remove the water residual from that part of the downstream fluid circuit of the 7 'cutting member. This part of the fluid circuit comprises the body of the valve unit 5, the chamber 6 of pre-infusion, filter 8 and associated pipes 5 ', 5' 'and 6'.

As shown in Figure 2, these means for remove the water comprise suction means, especially a pump 11, positioned along the discharge pipe 5 ', in an intermediate position along it or downstream of this last. The absorbed wastewater is transported in a container 12 collection or directly in the waste pipe.

The way the espresso machine works that forms the object of the present invention is as follows. While the coffee is being dispensed, the pump 2 is on, the 7 'cutting member is open and 7' 'cutting member is open closed. The water, which is pressurized between 8 and 10 bar by the pump, flows into the heating chamber 3 where it is heated to the desired temperature. From here, the water heated is pumped to the valve unit 5 and from there to a pre-infusion chamber 6, from which it is transported to filter 8 containing the coffee mixture. The coffee infusion produced in this way is dispensed through the holes 9 'in the filter holder 9 and is collected in the cup 13.

Once the coffee has been dispensed, the 7 'cutting member closes and pump 2 turns off. The same time, the cutting member 7 '' opens and the pump 11 is activated for a period of time long enough to ensure that the wastewater found in that part is absorbed of the circuit downstream of the cutting member 7 '. In addition to absorb residual water towards the discharge outlet, the action of pump suction 11 causes a pressure drop within the fluid circuit and this helps dry coffee grounds by evaporation

In a particularly preferred embodiment of the present invention, said suction means comprise a ejector 14. This ejector is coaxially housed within a suction chamber 15 formed along the pipe 5 'of discharge. A conduit 16 leading to the outside (for example, inside the collection container 12) extends away from the suction chamber 15, in a coaxial direction with ejector 14. Ejector 14 is in fluid communication with generator 4 of water vapor through a 4 'pipe. A valve 17 regulates the water vapor flow from generator 4 to the ejector 14.

The way the suction system works in This case is as follows. Once the coffee has been dispensed, when the 7 'cutting member has been closed and the 7' 'member of cut has opened, valve 17 also opens at the same time. Water vapor is thus supplied to ejector 14. The flow of water vapor that exits through the ejector 14 creates a fall of pressure in the suction chamber 15 that causes the wastewater be absorbed and finally discharged abroad through the duct 16. In this case, too, the pressure drop generated within the fluid circuit located downstream of member 7 'of cut makes all the water that has cut coffee grounds evaporate, finally causing the grounds to dry sufficiently to be easily removed from the filter.

In all embodiments of this invention, the machine can include a control unit designed to run the pumps and open and close the members of valve cut at appropriate times.

Needless to say, additional variant embodiments of the present invention can be conceived without thereby departing from the inventive concept on which it is based. For example, the means for removing residual water may comprise, in addition to the means described above, one or more devices for injecting compressed air or some other drying fluid into the fluid circuit located downstream of the cutting member 7 '. More specifically, these injector devices can be opened inside the pre-infusion chamber 6 and / or in the region of the filter 8. The flow of drying fluid on one side helps the wastewater to flow naturally and, on the other side, it favors evaporation of any water left along the walls of the circuit and in the grounds of
coffee.

According to an additional variant, said means for removing water may comprise, in addition to the already described above, means for heating the entire circuit of downstream of the cutting member 7 '. These means of heating, which should be able to raise the temperature of said fluid circuit up to 100 ° C or more, may consist of a set of heating elements surrounding said circuit or in a system of heat exchangers that extract heat from the water vapor generator 4.

It goes without saying that the realizations that are described above are simply realizations specific to the espresso machine that forms the object of the present invention, and those skilled in the art will be able to make any modifications that may be necessary in order to adapt it to specific applications, without leaving by this of the scope of protection claimed.

Claims (9)

1. Espresso coffee machine comprising a pump (2) for pumping water in a heating chamber (3) and a valve unit (5) located downstream of said heating chamber (3) and connected to said chamber (3 ) of heating by means of a pipe (3 ') that ends in an upper opening of said valve unit (5), said valve unit (5) having a first lower opening which is in fluid communication with a pipe (5) ') discharge and a second lower opening that is in fluid communication with a pre-infusion chamber (6), said pre-infusion chamber (6) being in fluid communication with the filter (8) via a pipe ( 6 ') of dispensing, the coffee machine comprising means (11, 14-15) for drying the coffee grounds that remain in the filter, characterized in that said means for removing residual water comprise suction means positioned along the discharge pipe (5 '), in a p intermediate ossification along it or downstream of the latter. 2. Espresso machine according to the claim 1 or 2, wherein a first cutting member (7 ') is movably housed in said upper opening of said unit (5) valve and in which a second cutting member (7 '') is movably housed in said first lower opening. 3. Espresso machine according to the claim 2, wherein said means for drying the grounds of coffee comprise means to remove wastewater from that part of the fluid circuit downstream of said first cutting member (7 '). 4. Espresso machine according to a any one of claims 1 to 3, wherein said means to remove residual water comprise an ejector (14) housed inside a suction chamber (15) formed along the discharge pipe (5 '). 5. Espresso machine according to the claim 4, wherein a conduit (16) leading to the outside it extends from said suction chamber (15). 6. Espresso machine according to the claim 4 or 5, wherein said ejector (14) is in fluid communication with a steam generator (4) by means of a pipe (4 ') for water vapor. 7. Espresso machine according to the claim 6, comprising a valve (17) for regulating the water vapor flow between the water vapor generator (4) and the ejector (14). 8. Espresso machine according to any one of claims 1 to 3, wherein said means of Suction are a pump (11). 9. Process to dry coffee grounds that they remain in the filter, which comprises the stage of removing the water residual once the coffee infusion has been dispensed, by suction medium or pressure drop.